03k24

Got an 03 with the exhaust cam lobes pitting. Was this the norm for the 03's?
Ive read other forums where it was talked about. Anyone have factory cam and followers they want to sell me after you did your cam upgrade? This is just my daily driver and would like to get a little more life out of it without a lot of expense.

Targa250R

Pretty common on the K20A3, K24A1, and K24A4 engines, unfortunately.

Is it causing a problem for you currently? If not, just ignore it and keep running the car.

03k24

Just ticking bad.....I put a heavier weight oil to give a little more protection. Its pitted on 3 of the lobes. One relatively bad.....i guess. Car still runs smooth and strong though. I have a friend with a k20 head that he took off and cams are good in it. Anyone know if the k20 cams/followers will work on a k24 head without any machine work? Id assume so since most performance cam upgrades list it as a k20/k24 set?????????

neal77

Well sorry to say i have no idea whether it would fit or not.

ilikehonda

what kind of oil are you using?


id get a good oil that has plenty of Zinc, phosp., etc. If you cant find a decent oil pick up some ZEP from Torco.

Mechanic

03K24: I agree with Targa250R's advice to ignore the problem and keep running the car. If you can replace the exhaust camshaft inexpensively, fine; if not, just drive the car conservatively. Others have driven with pitted cams for years and never realized it.

I'm curious about your car's maintenance history. Would you take a minute to describe it? Mileage? Oil (brand and weight)? Operating environment (stop & go, interstate, winters)? Thanks.

fin781

Im interested in the history as well, altough im not familiar with the k series, i would like to see why the cams pitt at an early age.

relativelyprime

I have a K20A3 with 85K on it and the lobe on the #3 exhaust cam was galling like crazy. I run Mobil 1 5W-20 synthetic and change it every 5-7K miles. In my mind it's not a 20 weight oil issue, like some sites say. EVERY other lobe in the engine was in perfect condition and I rarely put stress on the engine (daily driver mostly interstate). I had a local shop put a new cam in for $1000 before tax. Figured not too bad if I can get another 85 - 100K (or more would be nice) before I need another cam. The local stealership wanted quite a bit more. I was very disappointed after reading numerous posts of people with the same problem in the same Honda engines, however. Great car, but a cam should not go to crap in 85K miles. I'd say get it fixed. $1500 max is 3-4 new car payments. Make it last 12 months on that repair and it was still cheaper than buying a new car

Mechanic

I doubt there is any single fact that one can point to and say, "Ah, ha! That's the cause of camshaft galling in k-series motors." High mileage, engine modifications, maintenance histories, how a car has been driven -- all are potential factors in camshaft wear. There's also the possibility that the camshafts in question were poorly manufactured. Common heat treatment processes include annealing, precipitation strengthening, quenching, and tempering, any one on which, done improperly, may eventually result in some sort of failure over time. Engine lubrication (or, more correctly, improper lubrication) is also a potential factor in camshaft galling.

You've apparently ruled out engine oil weight as a factor, and you may be correct. That said, as you may know, Honda has always recommended 5W-30 weight oil for all of its higher performance motors (10W-30 for S2000 motors), and synthetic oil (also 5W-30 weight) for its turbocharged engines. Thus, I don't think you can rule out the possibility that inadequate lubrication -- oil shearing over time -- may be a proximate cause of camshaft galling in k-series engines.

WRT your point that the wear you experienced was limited to a single lobe and, therefore, you don't believe that the use of 5W-20 weight oil was the cause or contributed to the wear you experienced, again you may be correct. The other possibility, however, is that the one or more lobes were vulnerable to wear (for a variety of reasons) and oil shearing simply accelerated the process. Regarding this point, whenever someone raises this issue, I always ask what weight oil they used, and 5W-20 weight oil is mentioned most often (at least 9 times out of 10). Of course, that is the weight oil that Honda recommends for the K203A engine, so that's to be expected. Still, I think that engine oil weight pays a role in this sort of engine damage over time, and that's one of the reasons -- perhaps the most signficant reason -- that Honda specifically recommends 5W-30 weight oil for its higher performance K20A2 motors.

In summary, now that you've had one camshaft replaced, were I you, I wouldn't continue using 5W-20 weight engine oil when all engine-oil manufacturers' data sheets clearly indicate that 5W-30 weight oil provides significant additional HT/HS protection. It's the one potential wear factor you can control.

Targa250R

I agree. The rampant skepticism and tinfoil hat theories over the switch to 5W-20 have lead many to speculate or insist that it is the cause of the camshaft pitting problems, but it doesn't add up to me.

I personally suspect that the camshaft castings themselves are of poor quality or the surface finishing was done improperly by the manufacturer.

Honda specified 5W-20 in '01-02 for all F-series and some J-series engines, and in all J-series engines from '02 on. These engines were originally designed for and initially used 5W-30. None have shown the same camshaft pitting seen with the K-series.

If the camshafts are susceptible to premature wear, then they are faulty regardless of the oil used. I'd be willing to bet that there are a number of K20A3s, K24A1s, and K24A4s out there that have only seen 5W-30 for their entire service life and still have pitting on the cam lobes.

relativelyprime

I'm in the process of getting a metallurgical analysis done on the cam. I'll soon know if it was heat treated properly and those types of things. If it wasn't, Honda will hear about it. If it was, I'm running synthetic diesel oil from now on and hope to achieve 15mpg city/22 highway Right now I'm still running 5W-20 cause I still have some to use. Then I was thinking 15W-40 in the summer and 0W-40 or 5W-40 in the winter. Or would all of you with oil weight phobia just recommend 5W-30? I am asking you for advice so the "oil weight phobia" wasn't a huge slam.

Targa250R

You don't want to go too high on the viscosity as it can cause problems with the VTC and VTEC systems, and potentially the timing chain tensioner as well. The oil passages in these parts are pretty small. You also won't want to switch back to 5W-20 after extended use of a higher-viscosity oil because the oil consumption will likely increase.

With that said, a 5W-40 synthetic will probably work fine year-round.

Mechanic

"[T]infoil hat theories." I like that. I, however, think of myself as more of a Luddite than paranoid. And I'm ready to concede that your thoughts are undoubtedly much better informed than mine, but even after all this time ('02-'10) we are both still speculating WRT this issue.

Relativelyprime: You, sir, are a patriot for the cause. Heretofore, no one has been willing to actually invest in trying to determine whether the source of the problem was Nature (manufacturing) or Nurture (maintenance). WRT your question about the use of 5W-40 oil, I think you are going to the other extreme which may result in a different set of problems. Based upon Honda's recommendation for the current Si's and (coincidentially) recent UOAs you can find on bobsistheoilguy.com, 5W-30 seems compelling to me. See, e.g., http://www.bobistheoilguy.com/forums...49#Post2066849 and http://www.bobistheoilguy.com/forums...41#Post2039741)

LPED

I would tend to agree , my guess is it was some bad cam manufacturing either in hardness or material spec .
These are roller cams so oil weight being thin I don't see that, its not like there going outside of recommended weight specs .If it was oil 5w20 then why J30/35 don't have same thing and what about all other makes running 5w20 , its just about standard .

On side note there going to 0w20

SlowIntegraLS

on the 03 model year k series they had an issue with the hardening process on the exhaust cam lobes...any motor after 03 do not have this problem and the replacement cam shaft will not not prematurely wear either. some ppl have gotten away with just re adjusting the vavles and getting a lil more milage out of it but eventually it will get worse and end up messing up the roller rockers. I just replaced one today at work. im a tech a Honda dealership and we only see this issue in 03 model year k sereis.

5strong

I've got a 2010 Accord K24Z3 with 103000. Began hearing some lifter clatter. Assumed it was time to adjust the valves. Pulled valve cover and discovered exhaust lobes on 2 and 4 galled and pitted. Really made me sick, as I've babied this car. I'm immediately leaning toward defective workmanship. At the dealer now awaiting a Honda inspector and hopefully some restitution. I'm really glad to have found this and welcome any further advice and information.

nash123456

Hi I know this is an old thread but what was the outcome?